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schliz writes "Researchers have made headway into developing spintronic RAM by successfully transferring spin information from an electron to a more robust atomic nucleus and accessing the information 2,000 times in 100 seconds before it decayed (abstract). The demonstration was conducted using phosphorus-doped silicon in a highly magnetized, low-temperature environment (8.59 Tesla, -269.5 degrees Celsius). Other researchers have achieved spin lifetimes of 30 hours in a weaker magnetic field (0.3 Tesla)."

At long last, the Fox network can successfully document and store (some of) the enormous amounts of spin generated by its commentators. What I want to know is when will the spin^2 ram be ready so we can start working on the O'Reilly spin/spin found in his "spin* free zone"

Well, a spin-free (spin 0) particle would obviously be a Higgs Boson.

Therefore O'Reilly is the source of inertia, and has yet to be found in France or Switzerland.

Approximately 2 to 3 times the magnetic field strength of a typical MRI

You just need one of those Cellphone Head Protectors, and at $30 it's a real bargain. "Between 20% and 80% of the radiation emitted by a mobile phone is deposited in the user's head. The microwave radiation is absorbed by and actually penetrates the area around the head, some reaching an inch, to an inch and a half, into the brain. Protect yourself by ordering our radiation protector."

Or just use speakerphone like I do, so you don't have to hold the phone to ya head and kill brain cells. (drinks 30th be

If they wanted to induce hype, they would have used Fahrenheit (-453.1 degrees Fahrenheit).

I guess in Australia temperatures are usually measured in Celsius in non-science context, and thus this is the scale people are used to. So with "-269.5 degrees Celsius" everyone knows "damn cold", while with "3.65 Kelvin" most readers would just have said: "huh?"

And everyone who knows the Kelvin scale can easily calculate the Kelvin temperature (because temperature differences are the same in Kelvin and degrees Celsi

I'm not a physicist, so someone please answer my (stupid?) question. Why is that ground-breaking technologies ranging from quantum computing, super conductivity, to now this requires insane levels of cold? Is it because this is pure theoretical research, and that practical materiel science and engineering comes later?

Building a really big electromagnet requires superconducting materials because of the immense amount of current required to generate the electric field. If the material wasn’t a superconductor, the resistance would generate so much heat that it would burn up.

Also (replying to myself, sorry), for what it’s worth, if you think that’s “insanely cold” you’re looking at it from exactly the wrong perspective. Cold is just the absence of heat. It just has very, very little heat. Almost none, in fact... 0 degrees C, by contrast, could be called “insanely hot”.

Heat causes noise and interference. Plenty of examples exist. You know the ripples you see coming off pavement? Heat. Electronics generally become less reliable the hotter

There is that, but equally for applications that require no magnetic field, things that are hot have lots of energy. Energetic particles bouncing around everywhere couple to your meticulously-set-up experiment to the environment, destroying your isolated system [wikipedia.org] and removing the quantum effects you're utilizing.

For quantum computing, one of the requirements specified by the di Vincenzo criteria [ibm.com] are long decoherence times. Heat seriously reduces those.

At least some of those are because quantum decoherence [wikipedia.org] happens faster when temperature rises. The time before quantum behavior turns into normal classical behavior is inversely proportional to temperature in Kelvin. (I tried to find something sane on Wikipedia, but all relevant articles seem to be written for experts...)

A more general explanation could be that new stuff happens at very low energies and very high energies compared to what we're used to. Cold is just low energy.

Subtle or tricky quantum-mechanical effects are washed out or destroyed at higher temperatures (all of the atom's kinetic energy that is what we measure as temperature). So anything new and quantum mechanical is likely to be done near absolute zero, since that's the easiest environment to work in.

Regarding electron spins, there's a really good reason for the insane levels of cold - electron spin transitions require incredibly small energies. Some quick wiki-ing [wikipedia.org] leads me to a value of 159.3*10^-24 joules to change spin at the magnetic field strengths cited in the summary. If I had to take a guess, the researchers are trying to keep the kinetic energy of the atoms being tested below that energy threshold so that the spin doesn't change randomly with Brownian motion.